Objective To compare the clinical outcomes of all-arthroscopic suture bridge fixation and posteromedial approach open reduction and internal fixation with screws for avulsion fractures of the posterior cruciate ligament (PCL) attachment in the knee joint.

Methods A retrospective analysis was conducted on the clinical data of 45 patients with avulsion fractures of the PCL attachment in the knee who were admitted to the Orthopedics and Traumatology Joint Ward of Zhangjiagang Traditional Chinese Medicine Hospital of Jiangsu Province between April 2021 and July 2023. The patients were divided into arthroscopic group (undergoing all-arthroscopic suture bridge fixation) and open internal fixation group (undergoing posteromedial approach open reduction and internal fixation with screws) based on varied surgical approach they received. The operative time and length of hospital stay for both groups were recorded, and the Visual Analogue Scale (VAS) scores before surgery, at 1 month and 6 months after surgery were assessed. The International Knee Documentation Committee (IKDC) subjective score, Lysholm knee function score, and Hospital for Special Surgery (HSS) knee function score were used to evaluate knee function before surgery and at 6 months after surgery. At 6 months after surgery, the range of motion of the affected knee joint was recorded, and the posterior drawer test was performed to assess the degree of PCL injury.

Results None of 45 patients experienced vascular or nerve injury intraoperatively, and there were no postoperative wound infections. X-ray examinations conducted 3 days after surgery showed good reduction of the fractures. All patients were followed up for 6 months. There were statistically significant differences in operative time, length of hospital stay and VAS scores at 1 month after surgery between the two groups (P < 0.05). However, there were no statistically significant differences in preoperative IKDC scores, Lysholm function scores, HSS knee function scores, range of motion at 6 months after surgery, and HSS scores between the two groups (P>0.05). There were statistically significant differences in IKDC scores and Lysholm function scores between the two groups at 6 months after surgery (P < 0.05). At 6 months after surgery, there were 16 cases with grade I injury and 6 cases of grade II injury in the arthroscopic group, and 15 cases of grade I injury and 8 cases of grade II injury in the open internal fixation group. There was no statistically significant difference in the degree of PCL injury between the two groups (Z=-0.538, P=0.591).

Conclusion Both all-arthroscopic suture bridge fixation and posteromedial approach open reduction and internal fixation with screws can achieve satisfactory clinical outcomes in the treatment of avulsion fractures of the PCL attachment. However, arthroscopic surgery has shorter incision and hospital stays, and can relieve early postoperative knee pain, with more pronounced advantages in knee function recovery.